This year, private schools accounted for just over 20% of A-level maths entries, even though the sector only educates about 8% of the population.

They also account for almost half of the entries in less traditional modern languages - for example Chinese, or Portuguese.

Overall maths and science entries are increasing. There were 7,882 more entries in maths this year though smaller rises in physics and chemistry.

The increase was welcomed by Yvonne Baker, the chief executive of Stemnet, a group which works to encourage young people to take up maths and science.

She said: "It is very pleasing to see that the upward trend in the numbers taking maths and science at A-level is continuing.

"We are starting to see a real sea-change in young people's attitudes to STEM subjects which is crucial not only to the UK's future economic stability and global competitiveness, but to realising the breadth of opportunities STEM offers young people."

But we do not know how many children in more challenging circumstances and less good schools are heeding the government's call for more scientists, engineers, economists and mathematicians.

'Working harder'

German appears to be in a state of permanent decline, and a faster one than French, whereas Spanish and Portuguese are increasing in popularity, along with Chinese, Russian and Polish.

Exam board chiefs, who briefed journalists on the results, believe that children are adept at picking up the subtle messages about which subjects will open up opportunities for them in the future.

A-level results

A-level passes A-E up 0.3 percentage points to 97.5%

26.7% of entries awarded grade A, up from 25.9% last year

There were 7,882 more entries for maths and an increase of 1,382 entries for further maths

There were small increases in chemistry (811) and physics (1,340) but a slight decrease in biology entries

English and maths are still the most popular subjects, followed by biology

French and German entries declined, by 3.7% and 7.7% respectively

This is a crucial reason for their choice along with their enjoyment of the subject, says Greg Watson, chief executive of OCR.

"Students respond in intelligent ways to the job market and the signals they're getting, and there has been an awful lot of noise about scientific subjects," he said.

Children are working harder, and teachers are now more familiar with teaching A-levels, say the exam boards.

Mr Watson said: "There are many teachers who have been teaching these A-levels for several years and it is possible that their teaching has improved."

His counterpart from AQA exam board, Dr Mike Cresswell, said: "It's true that students are working harder.

"We shouldn't look for reasons to try to explain away the success.

"We don't do this in any other area."

'Harder next year'

The positive statistics may not end the perennial debate over whether A-levels have been "dumbed down".

The Conservatives fired an early shot last week, saying they would award more league table points for "harder" A-levels.

But the exam board chiefs shy away from this idea.

Greg Watson said: "Anything which threatens to distort young people's choices should be avoided.

"We haven't needed quotas to get more young people to study sciences."

Next year, A-levels are set to get harder. Or in exam-speak, "provide stretch and challenge".

Dr John Dunford, general secretary of the Association of School and College Leaders, says they will "cease to take students through the answer".

"We have been told the questions will be more difficult next year," he told journalists.

"Grades could go down. There will be a different style of questions: they will be more analytical."

An A* grade will also be introduced to enable universities to pick the brightest students from the large numbers now achieving As.

And exam boards said they were actively considering other options.

Jerry Jarvis, Managing Director of Edexcel, said: "We are looking at ways of discriminating or ranking figures quite regularly in discussions we have.

"In the future we may see complementary measures of performance.

"But grades have been around for a long time. The public have a feel for what is meant by grades."

He said there was no case for making A-levels harder because the pass rate was so high.

"We have to make sure we maintain the standard.

"It's not long ago that people were running 100 metres over 9.8 seconds."

A spokeswoman for the DCSF said: "Getting into university has always been a competitive process. Universities rightly decide their own admissions policies and can already ask for a student's actual marks, as well as considering their grades, Ucas forms and teachers' reports.

"The A* will help them identify the brightest candidates in future - and the new exams and Extended Projects will help students better demonstrate the full range of their skills."

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